So you’re in the mood for some Angry Birds action but after a while, you decide that it’s time to start working on your homework instead. Did you know that Rovio, the makers of Angry Birds, will still be virtually watching you and recording your GPS and WiFi location data? And it is far from the only app of its kind.

Researchers at MIT looked through several popular Android apps and found that many of them will indeed to collect private information about users even after they close the app. There have been many studies about the needless collection of private data for some apps, making harmless games and productivity software seem more voyeuristic than anything, but the issue of what happens after you close the app has been far less discussed.

Another example is the game Bowman, which will track users’ Web browsing history long after they’ve stopped playing. Also, WhatsApp, a popular substitute to the default texting app, scours user address books nonstop.

The study only looked at Android apps, presumably since they are more open and accessible, but this is no doubt an issue with the iPhone and iPad as well.

Of course, even on Android, developers are limited with what they can do with user data. Those who violate these policies will find their apps removed from Google Play entirely, but the point of this study is the privacy implications of even the most successful mobile games and apps.

These apps have legitimate reasons for collecting user information, but the question is whether or not it makes sense for that data collection to continue when users are not actively engaged with the app. The MIT researchers hope their findings will help shine a light on this excessive practice and lead to more privacy for the end users.